Abstract
Voltammetric measurements were performed for the transfers of Li+ and Na+ at an oil/water interface facilitated by neutral ionophores including 14-crown-4 derivatives. For the organic solvent, nitrobenzene, o-nitrophenyloctylether (NPOE) and o-nitrophenylphenylether (NPPE) were examined. The interface between water and NPPE containing 20mM dibenzyl-14-crown-4 was found to serve best for the ion-selective-electrode (ISE) surface for the voltammetric determination of Li+. A test of this voltammetric Li+-ISE using artificial serum showed that the interference from a large amount (ca. 140mM) of Na+ in blood can be easily avoided by detecting the Na+ concentration simultaneously with the same electrode.
